One of radiographic inspection apparatuses is a computed tomography (CT) apparatus. The CT apparatus comprises an X-ray tube for radiating X-ray fan beams, and a radiation detector comprising a large number of radiation detection elements arranged in parallel. The X-ray tube and the radiation detector are arranged oppositely to each other with an object to be measured at center. X-ray fan beams radiated from the X-ray tube pass through the object to be measured, and are detected by the radiation detector. With every radiation having a changed angle, X-ray absorption data are collected to calculate X-ray absorbance at each position in each cross section of the object by computer analysis, thereby forming an image based on the X-ray absorbance. The radiation detector may be a detector comprising a combination of a scintillator array and silicon photodiodes, or a detector comprising a scintillator array and photomultiplier tubes.
As a method for producing such a scintillator array, JP 2000-241554 A discloses a method comprising disposing light-emitting elements on an adhesive sheet, placing a frame enclosing the light-emitting elements on the adhesive sheet, introducing an epoxy resin containing rutile-type titanium oxide powder for a light-reflecting layer into the frame to cover the light-emitting elements with the resin, curing the resin by heating, removing the adhesive sheet and the frame, and machining the cured body to form a scintillator array having a predetermined shape. However, this method suffers a large number of steps, because dissolving and washing steps are needed to peel the adhesive sheet.
JP 2004-3970 A discloses a method comprising covering a comb-shaped scintillator wafer with a polyester resin containing rutile-type titanium oxide, and then curing the resin by heating to form a light-reflecting layer. A reservoir frame is placed around the scintillator wafer to prevent the resin from flowing out. However, this method does not use an adhesive sheet for fixing the comb-shaped scintillator wafer.
JP 4-273087 A discloses a method for producing a scintillator array comprising disposing scintillator substrates with predetermined gaps on an adhesive sheet in a frame, introducing a liquid light-reflecting resin into the frame such that the liquid light-reflecting resin enters gaps between the scintillator substrates, curing the liquid resin, and removing the adhesive sheet. However, when the resin is cured on the adhesive sheet, dissolving and washing steps are needed to peel the adhesive sheet, resulting in an increased number of steps.
JP 2000-98041 A discloses a method for producing a radiation detector comprising attaching a light-emitting layer to a first ultraviolet-ray-sensitive adhesive film, forming lattice-patterned grooves reaching the adhesive film in the light-emitting layer by laser beams, attaching a second adhesive film to an opposite surface of the light-emitting layer to the first adhesive film, removing the first adhesive film by radiating ultraviolet rays, and subjecting at least one surface of the light-emitting layer to a surface treatment for improving light transmission to a photo-detector. However, this method does not use a member for supporting the second adhesive film. When the second adhesive film is curved, light-emitting layers separate from each other by the grooves are likely displaced before the resin-coating step.
JP 2003-14852 A discloses a method for producing a multi-channel radiation detector, in which pluralities of radiation detectors each constituted by a laminate of a scintillator and a light-detecting semiconductor element are arranged, comprising the steps of attaching one surface of a scintillator wafer to a holding sheet, slicing the scintillator wafer attached to the holding sheet with a predetermined interval to form gaps, pouring a white mixture containing rutile-type titanium oxide and a resin onto the sliced scintillator such that the white mixture fills the gaps and spaces around the scintillator, curing the resin to make pluralities of scintillators integral with the white mixture, machining pluralities of the integrated scintillators to a predetermined size, attaching a light-reflecting layer comprising rutile-type titanium oxide and a resin to one surface of each scintillator, and attaching a light-detecting semiconductor element to the other side of each scintillator. Used as the holding sheet is a foamed sheet. However, when the resin is cured on the foamed sheet, dissolving and washing steps are needed to peel the adhesive sheet, resulting in an increased number of steps.